The present invention relates to a watercraft for travelling along a surface of a body of water. The watercraft may be jet-propelled watercraft such as personal watercraft or inboard or outboard powered boats.
Watercraft of the type herein contemplated comprise a hull for buoyantly supporting the watercraft on the surface of a body of water and an engine carried by the hull therein. A driveshaft is coupled with an output shaft of the engine to rotate a propelling structure connected to an axial end portion of the driveshaft so as to propel the watercraft along-the surface of the body of water.
The engines of these watercraft are usually mounted on shock absorbing mounts that incorporate resiliently deformable material for dampening the transmission of vibrations from the engine to the hull. The resiliently deformable material of these mounts allows the engine to move slightly with respect to the hull. When the driveshaft and output shaft are coupled within the engine""s coupling structure, the relative motion of the engine will cause the output shaft to abut against the end of the driveshaft which creates a hammering effect that can damage the engine as well as other components of the watercraft, such as the propelling structure.
To minimize this hammering effect, a rubber endcap has been placed on an axial end portion of the driveshaft close to the engine to cushion the abutment with the output shaft. However, the endcap is placed on the driveshaft with a friction-type fit which is not particularly secure and may fall off the driveshaft. This arrangement has been found to be suitable for engines wherein the coupling structure is external to the engine""s outer casing because it is easier for the installing technician to visually verify the placement of the endcap as the driveshaft is inserted into the coupling structure. However, such an arrangement is not well-suited for an arrangement wherein the coupling structure is internal to the engine""s casing. The driveshaft with the rubber endcap is placed blindly therein and it is more difficult for the technician to visually verify that the endcap is properly positioned as it is being inserted into the coupling structure via the opening in the engine""s outer casing. Thus, it is more likely that the endcap may be knocked off or oriented improperly during installation.
Accordingly, there is a need for an endcap which is fixedly secured on the end of the driveshaft so a proper placement within the coupling structure is guaranteed, regardless of a visual confirmation. This will ensure that the engine and associated components will not be damaged if abutment between the driveshaft and the coupled output shaft occurs.
Further, because known endcaps are not securely and captively placed on the driveshaft, endcaps are likely to fall off the driveshaft during handling and transport within the manufacturing plant. Accordingly, there is a need for an endcap which is fixedly secured on the end of the driveshaft so that the endcap is less likely to fall off and become displaced.
It is an object of the present invention to couple the driveshaft and output shaft together while meeting the above-described needs.
In accordance with one aspect of the present invention, this objective is achieved by providing a watercraft for travelling along a surface of a body of water. The watercraft comprises a hull for buoyantly supporting the watercraft on the surface of the body of water. An engine is carried by the hull and comprises an outer casing, a rotatable output shaft, and a coupling structure provided on one end of the output shaft for rotation therewith. The coupling structure has a driveshaft receiving bore.
A driveshaft has an engine connecting axial end portion and a propelling structure connecting axial end portion. The engine connecting end portion provides a first cooperating interlocking structure. A resiliently deformable cushioning structure has a second cooperating interlocking structure and is mounted to the engine connecting axial end portion of the driveshaft with the first and second cooperating interlocking structures interlocking with one another in a cooperating relationship to secure the cushioning structure on the engine connecting axial end portion.
The engine connecting axial end portion of the driveshaft with the cushioning structure secured thereon is inserted into the driveshaft receiving bore of the coupling structure. The coupling structure couples the output shaft and the drive shaft together so that powered rotation of the output shaft rotates the driveshaft via the coupling structure. The cushioning structure is positioned between the engine connecting axial end portion and abuttable structure within the driveshaft receiving bore such that the cushioning structure prevents the engine connecting axial end portion from abutting directly against the abuttable structure during relative movement of the engine and the driveshaft towards one another.
A propelling structure is operatively connected to the propelling structure axial end portion of the driveshaft such that powered rotation of the output shaft rotates the propelling structure via the driveshaft. The propelling structure is constructed and arranged to displace water during rotation thereof so as to propel the watercraft along the surface of the body of water.
In accordance with another aspect of the present invention, the engine carried by the hull comprises an outer casing having a supply of lubricant contained therein. The output shaft has structure defining a fluid path communicating the supply of lubricant to the driveshaft receiving bore such that during generation of power, the lubricant flows along the fluid path to the driveshaft receiving bore of the coupling structure. The driveshaft has an engine connecting axial end portion and a propelling structure connecting axial end portion. The engine connecting axial end portion has one or more generally radially extending lubricant distributing grooves formed thereon when the cushioning structure is not provided.
In accordance with another aspect of the present invention, the engine connecting axial end portion of the driveshaft is inserted into the driveshaft receiving bore of the coupling structure such that the coupling structure couples the output shaft and the driveshaft together so that powered rotation of the output shaft rotates the driveshaft via the coupling structure. The one or more generally radially extending lubricant distributing grooves are positioned in communication with the fluid path so that the lubricant flowing into the driveshaft receiving space flows into the one or more lubricant distributing grooves. Each of the one or more lubricant distributing grooves is configured to distribute the lubricant radially within the driveshaft receiving bore by centrifugal force during the rotation of the driveshaft and the output shaft.
In accordance with another aspect of the present invention, the objective is achieved by providing a driveshaft assembly for use in a vehicle having an engine with an output shaft. The driveshaft assembly comprises a driveshaft having an engine connecting axial end portion. The engine connecting end portion provides a first cooperating interlocking structure. A resiliently deformable cushioning structure having a second cooperating interlocking structure is mounted to the engine connecting axial end portion of the driveshaft, the first and second cooperating interlocking structures interlocking with one another in a cooperating relationship to secure the cushioning structure on the engine connecting axial end portion. The driveshaft further comprises a propelling structure connecting axial end portion. The propelling structure axial end portion is adapted to be operatively connected to a propelling structure such that powered rotation of the output shaft rotates the propelling structure via the driveshaft.
In accordance with another aspect of the present invention, a driveshaft is provided for use in a vehicle having an engine with an output shaft, the output shaft having structure defining a fluid path communicating a supply of lubricant contained within the engine. The driveshaft comprises an engine connecting axial end portion having one or more generally radially extending lubricant distributing grooves formed thereon. The engine connecting axial end portion of the driveshaft is adapted to be coupled with the output shaft so that powered rotation of the output shaft is transmitted to the driveshaft and the one or more generally radially extending lubricant distributing grooves are positioned in communication with the fluid path so that the lubricant flows into the one or more lubricant distributing grooves. Each of the one or more lubricant distributing grooves is configured to distribute the lubricant radially by centrifugal force during the rotation of the driveshaft and the output shaft. The driveshaft further includes a propelling structure connecting axial end portion. The propelling structure axial end portion is adapted to be operatively connected to a propelling structure such that powered rotation of the output shaft rotates the propelling structure via the driveshaft.
These and other objects, features, and advantages of this invention will become apparent from the following detailed description when taken into conjunction with the accompanying drawings, which are a part of this disclosure and which illustrate, by way of example, the principles of this invention.